Apparatus for producing cold electric discharges



J. KUHLENSCHMIDT.

APPARATUS FOR PRODUCING C 0LD ELECTRIC DISCHARGES.

APPLICATION FILED JULY Z5, 1922.

Patented Dec. 5, 1922 Patented Dec. 5, 1922 UNITED STATES J'OHA-NNESKUHLENSCHMIDT, OF BERLIN-HOHEN'SCHONHAUSEN, GERMANY.

APPARATUS non rnonocme Application filed July 25,

To all whom it may concern Be it known that I, JoHANNns KUHLEN- SCHMIDT,a citizen of the German Republic, residing at Berlin-Hohenschonhausen,Germany, have invented certain new and useful Improvements. in Apparatusfor Producing Cold Electric Discharges, of which the following is aspecification.

This invention has reference to means for the production of silent orcold electric discharges, such as are used among other purposes,particularly for the production of ozone, for the sterilization ofliquids, for the artificial ageing of alcoholic liquors and the like,and for other important uses.

The invention has for one of its objects to provide an apparatus of thekind referred to which is of simple construction, canbe cheaplymanufactured, and is reliable and highly eflicient in operation, andwhich, when used-for example for the production of ozone, is capable ofyielding a higher output of ozone in proportion to the amount of 'wattsconsumed, and in regard to the size of the apparatus, and the amount ofmaterial employed than the devices heretofore employed for thepurpose,vand which moreover may be operated without the necessity of aspecial cooling agent, and is adapted to a greater variety of uses thanprevious devices of the kind.

Other objects and advantages of the invention will appear from thefollowing specification and the annexed drawings, showing by way ofexample various forms of embodiments of the principles of my invention.

In the drawin :Figure 1 is a longitudinal vertical sectlonal View of anapparatus according to my invention ;Figure 2 is a similar verticallongitudinal section of a somewhat modified form of construction and ina more diagrammatic manner ;Figure 3 is a cross section through one pairof the electrodes employed in connection with my invention ;--Figure 4is a perspective view with part vertical section of a modifiedconstruction of two electrodes.-Figure 5 illustrates diagrammaticallyanother form of arrangement of the electrodes; and Figures 6 and 7represent in top plan view twosupporting rings for the electrodes to beused for example in the construction of apparatus shown in Figure. 1..

The form of apparatus disclosed in Figure 1 may be attached to a wallboard or the COLD ELECTRIC DISCHARGES.

1922. Serial No. 577,469.

like by means of two insulators 1, 1'. To the free ends of theinsulators fittings 3, 3' are secured of identical construction; and theconstruction of the entire apparatus is such that the upper end of theapparatus is a substantially exact counterpart both as regardsarrangement. as well as shape of the parts of the lower portion thereof,so that the several parts may be easily inverted and be used in anotherposition with regard to the horizontal plane of symmetry.

The fittings 3, 3 are provided with three apertures. The confrontingapertures or openings 4, 4 serve for the reception of the electrodes 5of which in the form of construction shown herewith, four are used. Thetwo middle electrodes 5 and 5 are shaped as hollow walled tubes. Theinner electrode 5 possesses the shape of a closed tube with solid walls.The outer electrode 5 is constructed as a cylinder or tube with solidwalls which is surrounded at its outside by. wire gauze or a metalliccoating 22. The walls of all electrodes are made of suitable di-electricmaterial, such as glass for instance, and I preferably employa kind ofglasswhich allows the shortwa'ved rays of light (Geissler-liglit) whichoccur in the manipulation of the apparatus, to pass throughsubstantially unaltered.

The central or interior electrode 5 projects upwards and downwards fromthe fittings 3, 3, the electrode being preferably conducted throughstufiing boxes 6, 6' in the lids or-covers 7, 7 or other closures of therespective fittings 3, 3. Above and below the ends of the electrodes 5and 5 cavities 8, 8' remain in the fittings 3, 3, short tubes 9, 9'"projecting laterally from the fittings and being connected to thecavities 8, 8'. These tubular projections serve for the mounting ofconductors for the fluids to be treated in the apparatus, of which I maymention as instances air, -water, spiritual liquors and the like.

The electrodes 5 and 5 are supported in the fittings 3, 3 by means ofupper supporting rings 10, 11 and lower supporting rings 10, 11'. Allthese rings may 'be screwed from the outside into the respective bore ofthe fitting after removal of the lids 7, 7..

The rings are provided with projections 12, i

13 by means of which the concentric position of the electrodes issecured. All the supporting rings are moreover provided with all partsof the inner walls.

with recesses or connecting passages 14, 15

which allow of the passage of the fluid entering for example in thedirection of the respective arrow into the lower tubular projection, andinto the annular spaces 16, 17 and 18 between the electrodes 5, 5 5 and5, and also permit the escape from these annular spaces and into theupper cavity 8 and thence through the tubular projection 9 in thedirection of the arrow, and into the conduit connected or communicatingtherewith. In this conduit or in the conduit communicating with thelower tubular projection 9' a blower, fan or the like may be mounted forthe purpose of causing the fluid to be treated by the apparatus to passthrough the apparatus in the manner indicated.

The upper and lower ends of the tube which corresponds to the outerelectrode 5 and which is preferably also made of glass is secured in thefittings 3, 3 by means of tightening rings 21, 21. In its middle portion the tube is provided with a casing or sleeve of wire gauze 22 inclose contact with its outer surface, and which extends upwards anddownwards to a distance from the fitting 3, 3 which corresponds to thetension of the current employed for the feeding of the apparatus. Thesleeve 22 is surrounded by a clamping ring 23 the screw 24 of which isconnected to a grounded conductor 25. Another conductor 26 is like wiserounded, and is connected by means of a c amping screw 27 to a cap 28mounted upon the lower end of the inner electrode 5. This cap isconnected by a platinum pin 29 secured by melting in the correspondingend of the electrode to a wire 30 which asses through the interior ofthe electrode in contact with a filler 31 in the interior thereof and towhich it is electrically coninected. This filling material consists {ofloose, finely granular electrically conducting material which iscontained in the electrode tube up to the limits marked in the draw-.

ings, and in such a-manner that the filler makes a perfect contactwithin these marks The position of the filler within the limitsindicated is secured by packing material 32, 32' which fills the spacebetween the confines of the filler and the ends of the electrode tube.The packing consists preferably of glass wool.

In a similar manner the electrodes 5 and 5 are constructed. In theseelectrodes the filling material 31 is arranged in the hollow walls ofthe glass cylinders constituting the electrode bodies or in the glasstubes of the electrodes. The connection with the current admitting meansfor the electrodes is in this case likewise effected by means of caps28, 28 of metal which are mounted at one end of the electrode tubes, andwhich are connected to a platinum pin 29 and 29 respectively secured tothe glass wall by being melted in, the said pins being electricallyconnected by a wire to the filling material. The end carrying the metalcap 28 of the outer one of the the two electrodes is in the constructionshown by way of example, the lower end,-while the electrode 5 carriesthe cap 28 at its upper end. The caps 28 and 28 are directlyelectrically connected to the corresponding supporting rings 11' and 10respectively. These rings are made of metal, so that they effect theelectric connection of the filler with the fittings 3, 3. To the upperfitting 3 and by means of the screw 35 a wire 36 is secured which isconnected to the positive terminal 37 of the secondary of a transformer39 the negative terminal of which is connected by a wire 41 at the point42 to the lower fitting 3' by means of which the electric connection ofthe filler 31 of the electrode 5 with the negative terminal 40-of thetransformer is established. The primary 43 of the transformer isconnected to a source of alternate current 44. The operating voltageamounts for instance to 5000 to 25000 volts.

As filling material for the electrodes loosely arranged metal chips maypreferably be used, and particularly short turning of aluminium. Alsocoarse metallic filings and'wire chips and interlacingly arranged piecesof wire gauze are suitable.

F urthermbre, leaden shot or any mass consisting of globular orsimilarly shaped small .bodies of other metals constitute a good fillingmaterial. The spheres of filling mate rial of this latter kind shouldhave a diameter of about one millimeter. It is of importance for thesatisfactory operation of the filling material that its articles shouldbe such as to leave cavities etween them, and that in connectiontherewith projecting parts, either as tips or as more or less roundedprojections are formed, and furthermore that the materials should besuch as to closely hug the walls of the hollow bodies of the electrodes,and in view thereof loose fillers are to be preferred. After theintroduction of the fillers and of the packing of glass wool theelectrodes are evacuated, and are then hermetically closed by melting orthe like.

Instead of the outer electrode 5 consisting of a glass tube withmetallic coating I may also use a hollow tubular electrode the filler ofwhich takes the place of the wire gauze coating 22. In this case theouter electrode, however, does not need to be evacuated; nor is thisnecessary for the inner electrode 5. Furthermore. the electrodes may beof other type as specified. 4

The apparatus may also consist of more or less than four electrodesinserted into each other, as appears from Figure 2. In

this figure I have shown for instance diagrammatically an apparatusprovided with five electrodes. In this case the inner electrode 5 whichalso presents a closed tube is .ed .to the negative terminal of thetrans- 10 former. The electrode 5 disposed between the electrodes 5 and5 and the outer electrode 5 which may also be replaced by a glasscylinder with wire coating, however, are grounded. The electrode 5 maybe entirely dispensed with, but it is of importance that the outerelectrode5 and the inner electrode 5 should be grounded.

If the apparatus, instead of consisting of telescopingly arrangedtubular electrodes is constructed of-plate shaped electrodes in themanner shown in figure 4 the two outer electrodes 5 and 5 and theinnermost electrode 5, as indicated in Figure 5, are grounded, thelatter electrode, however, may

e entirely dispensed with. Between the grounded electrodes in this casealso the electrodes 5*" and 5" connected to the terminals of thetransformer are arranged.

The construction of the plate shaped electrodes is substantially thesame as that of the tubular electrodes. They constitute a closed hollowbody forming a rectangular flat box with solid walls of which the. sidewalls 46-and 47 possessing the greatest extension, are confrontingly andsubstantially parallelly arranged at a slight distance from each other.The upper and lower longitudinal edges of the electrodes are in thiscase also provided with a metal can 28 each which is electricallyconnected to the filler 31 which in the case of Figure 4 consists ofshot. The plate shaped electrodes are also evacuated after having beencharged with the filler, and are then air tightly closed. In this kindof apparatus consisting of plate shaped electrodes the two groundedouter electrodes may also be replaced by plates of glass or the likecoated at the outside with wire gauze or the like.

The rounding of some of the electrodes, prefera ly of the outer andinner ones, or the surrounding of the electrodes with grounded radiatingsurfaces results in a considerably improved efiiclency of the apparatuswhich, when the apparatus 1s used as an ozone generator, produces aconslderably increased output of ozone 1n proportion to the consumptionof watts by the apparatus. Besides, with all conditions being otherwiseequal a considerablv higher yield of ozone is obtalned by means ofpartially grounded electrodes according to this invention than in thecase of the apparatus heretofore employed and of otherwlse the samedimensions and at the same costs of manufacture. The superior action ofthe apparatus is also aided considerably by the special formation andconstruction of the electrodes. It is of importance in this respect thatthe cavities of the electrodes, containing the filling material, areevacuated in combination with the vformation and nature of theconducting filler. The innumerable particles of the filler which aredistributed over the interior of the electrode and are separated byevacuated spaces assist the production of the radiation in the shape ofdark or silent discharges which are particluarly favorable for thegeneration of ozone. In this connection the many pointed tips andprojections of the particles are also of importance. In view of thefiller completely permeating the cavity of the electrode the dischargesreferred totake place within the entire space of the cavity. In thenumerous small spaces the Geissler light may be very well developedwhich is especially favorable for the production of ozone. Furthermorethan that, by means of the close contact effected with the inner wallsof the electrodes by the said mass the particles of which are in goodheat conducting connection, a uniform distribution and good eduction ofthe heat is obtained, and by this means excessive heating and localstagnation of heat are avoided. so that an apparatus of this kind, ifequally cooled, may be considerably more strained and taxed than theozone producers ordinarily employed; and it may also be operated withoutspecial cooling with all other conditions remaining equal. The-chargingand uniform' distribution of the loose filler does not present anydifiiculties even in the case of not exactly trued or calibrated tubes,which is of importance, particularly in case the electrodes are formedof the difiicultly workable quartz glass. Inasmuch as with the superiordevelopment of the light in the interior of the electrodes, whichassists the generation of ozone and the increase of efiiciency theelectrodes operate with satisfactory conditions even in those cases,where no light phenomena canbe produced in the spaces between theelectrodes to assist the production of ozone (as is the case in thetreatment of liquids conducted through the said spaces) the electrodesmay be used with great advantage for the artificial ageing of spiritualliquors and the like. It is also of importance in this connection that,on account of the decreased and uniform heating and heat eduction thebetter adapt the invention to various conditions of utllization, all ofwhich being within the scope of my invention as set forth and clearlypointed out in the claims hereunto appended.

I claim:

1. Apparatus for producing cold electric discharges, particularly forthe generation of ozone, comprising a source of high tension current, atleast three electrodes so arranged relatively to each other as toconstitute outer and inner electrodes, to form spaces between themadapted for the reception of a fluid, at least two of said electrodesbeing connected to different terminals of said source of current, and atleast-one of the other of said electrodes being grounded.

2. Apparatus for producing cold electric discharges, particularly forthe generation of ozone, comprising a source of high ten- S1011 current,at least three electrodes so arranged relatively to each other as toconstitute outer and inner electrodes, the electrodes being arranged inpairs and spaced from each other, and means adapted to conduct a fluidthrough the spaces between said electrodes, at least two of saidelectrodes being connected to different terminals of said source ofcurrent, and the innermost of said electrodes being grounded.

3. Apparatus for producing cold electric discharges, particularly forthe generation of ozone, comprising a source of high tension current, aplurality of electrodes arranged relatively to each other, so as toconstitute two outer and at least two inner electrodes, each two of saidelectrodes being spaced from each other, and adapted for the passage ofa fluid through the intervening space, at least two of said electrodesbeing connected to different poles of said source of current, the twoouter electrodes being grounded.

4. Apparatus for producing cold electric discharges, particularly forthe generation of ozone, comprising a source of high tension current atleast three electrodes concentrically arranged, and constituting outerand inner electrodes respectively, and adapted to leave annular spacesbetween each two of said electrodes, at least two of said electrodesbeing connected to different, poles of said source of current, one ofthe said outer elec trodes and one of said inner electrodes beinggrounded.

5. Apparatus for producing cold electric discharges, particularly forthe generation of ozone, comprising a source of high tension current, atleast three tubular electrodes concentrically arranged, soas toconstitute an outermost and an innermost electrode, and to form annularspaces between them, at least two of said electrodes being connected todifferent poles of said source of current, the outermost and theinnermost electrode being grounded.

6. Apparatus for producing cold electric discharges, particularly forthe generation of ozone, comprising at least three electrodes soarranged relatively to" each other as to constitute outer and innerelectrodes and an outermost, an innermost and two middle electrodes andto form three annular spaces between them, the outermost and theinnermost electrode being grounded, and means to connect said middleelectrodes to two different poles of a high tension current.

source.

8. Apparatus for producing cold electric discharges, particularly forthe generation of ozone, comprising a source of high tension current, aplurality of electrodes so arranged relatively to each other as toconstitute outer and inner electrodes, and to form spaces between themadapted for the passage of a fluid, some of said electrodes con nectedto different-poles of said source of current, other of said electrodesbeing grounded, the electrodes electrically connected to the source ofcurrent comprising evacuated hollow bodies of dielectric material withtwo opposite walls having comparatively considerable surface area, andcontaining an electric conductor in contact with the two walls of thehollow body for the greater part of their surface area.

9. In an apparatus for producing cold electric discharges, particularlyfor the generatlon of ozone, at least three electrodes, spaced apartfrom each other, means for connecting said electrodes to three diflerentpotentials and means for efl'ecting the passage of a fluid between saidelectrodes.

10. In an apparatus for producing cold electric discharges, particularlyfor the generatlon of ozone, a plurality of electrodes arranged inpairs, spaces between the electrodes of each pair, adapted for thepassage of a fluid, at least two of said electrodes be- .ing chargedwith two different electric potentials, and others of said electrodesbeing charged with a third potential.

11. In an apparatus for producing cold electric discharges, a pluralityof electrodes, at least two of said electrodes consisting of evacuatedhollow bodies with walls of dielectric material, and having two oppositeWalls of greater surface area, an electrically conducting mass containedin said hollow walls,

bodies and in contact with both opposite said electrodes beingsufliciently spaced from each other to form passage for a fluid betweenthem, means for connecting at least'two of said electrodes to twodifferent high tension potentials and means for connecting at least oneof the other electrodes to a third potential. I

12. In an apparatus for producing cold electric discharges, a pluralityof tubular electrodes concentrically arranged so as to constitute anoutermost, an innermost electrode and middle electrodes, and to formspaces between them, means for conducting a fluid through said spaces,at least two of said electrodes consisting of evacuated hollow bodieswith walls of dielectric material, and having two opposite walls ofgreater surface area, an electrically conducting mass contained in saidhollow bodies and in contact With both opposite walls, means forconnecting some of said middle electrodes to different terminals of asource of high tension current and means for grounding said outer andinnermost electrodes,

13. In an apparatus for the production of cold electric discharges, aplurality of concentrically arranged tubular electrodes of differentdiameter, consisting of evacuated hollow bodies of glass and of annularcross section, an innermost electrode comprising a cylindrical hollowglass body mounted at the interior of the tubular electrode of smallestdiameter, the said electrodes being so arranged relatively to eachother, as to have the greater portion of their walls in substantiallyparallel confronting relation to each other, thereby forming spaces ofannular cross section adapted for the passage of a fluid, and conductingsubstances within said electrodes and in contact with the saidconfronting walls of each individual electrode.

14. In an apparatus for the production of cold electric discharges, aplurality of concentrically arranged tubular electrodes of differentdiameter,-consisting of evacuated hollow bodies of glass and of annularcross section, an innermost electrode comprising a cylindrical hollowglass bodymounted at the interior of the tubular electrode of smallestdiameter, the said electrodes being so arranged relatively to eachother, as to have the greater portion of their walls in substantiallyparallel confronting relation to each other, thereby forming spaces ofannular cross section adapted for the assage of a fluid, and a fillingof metallic e ips contained in said electrodes.

15. In an apparatus for the production of cold electric discharges, apair of electrodes, each electrode of said pair consisting of anevacuated hollow body of dielectric material with nearer and fartherspacedly opposite walls, and an electrically conducting mass containedin said electrodes in contact with the inner surfaces of the neareropposite wall portions of said electrodes.

16. In an apparatus for the production of cold electric discharges, apair of electrodes,

each electrode of said pair consisting of an evacuated hollow glassbody, and. a loose mass of small metallic particles contained in saidhollow body. 1

17. In an apparatus for the production of cold electric discharges, apair of electrodes, each electrode of said pair consisting of anevacuated hollow glass body, and a filler of shot in said hollow body.

-18. In an apparatus for the production of cold electric discharges, apair ofelectrodes, each electrode of said pair consisting of anevacuated hollow glass body, and a inaiss of aluminium turnings in saidhollow 19. In an apparatus for the production of cold electric dischares, a pair of electrodes, each electrode of sai pair of electrodescomprising a tube of dielectric material, one of the electrode tubeshaving hollow evacuated walls, a loosely arranged metallic mass withinthe hollow walls of said electrode and'in contact with the innersurfaces of the confronting cylindrical wall portions, and means foreffecting the electric connection of 1said metallic mass with anelectric potentia 20. In an apparatus for the production of coldelectricdischarges, a pair of electrodes,

each electrode of said pair of electrodes comprising a tube ofdielectric material, one of the electrode tubes having hollow evacuatedwalls, a partial filling of a loose mass of metallic particles, withinthe hollow walls of said electrode and in contact with the innersurfaces of the confronting cylindrical wall portions and means foreffecting the electric connection of said metallic mass with an electricpotential.

21. In an apparatus for producing cold electric. discharges,particularly for the generation of ozone, three tubular electrodessubstantially concentrically arranged so as to form narrow spacesbetween them, means for allowing a fluid to pass'said spaces, saidelectrodes comprising hollow glass bodies having cylindrical side walls,the inner faces of which being in near opposite relation to each other,said hollow bodies partially filled with a loose mass of small metallicparticles in contact with the greater portion of said inner faces, twoof said electrodes being evacuated, means for connecting the mass ofmetallic particles of each of said evacuated electrodes to a pole of asource of high tension current, and means for grounding the other one ofsaid three electrodes.

22. In an apparatus for producingcold electric discharges, particularlyfor the generation of ozone, three tubular electrodes substantiallyconcentrically arrangedso as to form narrow spacesbetween-them, meansfor allowing a fluid to pass said spaces, said electrodes comprisinhollow glass bodies having cylindrical si e walls, the inner faces ofwhich being in near opposite relation to each other, said hollow bodiespartially filled with a loose mass of small metallic particles incontact with the greater portion of said inner faces, two of saidelectrodes being evacuated, means for connecting the mass of metallicparticles of each of said evacuated electrodes to a pole of a source ofhigh tention current, a fourth cylindrical electrode surrounding saidthree electrodes so as to form a further space adaptedto receive afluid, and means for grounding said cylindrical electrode.

23. In an apparatus for producing cold electric discharges, particularlyfor the generation of ozone, three tubular electrodes substantiallyconcentrically arranged, so as to constitute an outer, an innermost anda middle-electrode, and forming comparatively narrow spaces between themadapted to allow a fluid to pass therethrough, said electrodes comprisinhollow glass bodies having cylindrical side walls, the inner faces ofwhich being in near opposite relation to each other, said hollow bodiespartially filled with a loose mass of small metallic particles incontact with the greater portion of said inner faces, said outer andmiddle electrode being evacuated, means for connecting said masses ofmetallic particles of said outer and middle electrode to differentterminals of a sourc'eof high tension current, a glass cylinder spacedlysurrounding said outer electrode so as to form a further space adaptedto allow the passage of a fluid, a metallic coating on the outer side ofsaid glass cylinder, and means for grounding said coating and the massof metallic particles in said innermost electrode.

24:. As an article of manufacture, an electrode for apparatus forproducing cold electric discharges, comprising a tubular body of glass,having a hollow'evacuated cylin drical wall portion, said wall portionbeing formed of an inner and an outerwall having the greatest portion oftheir sides in substantially parallel confronting relation to eachother, a loose mass of small metallic particles contained in said hollowwall portion in contact with the greatest part of the inner sides ofsaid inner and outer walls, and means for electrically connecting saidmass to an outer electric potential.

25. As an article of manufacture an electrode for apparatus for producincold electric discharges, comprising a tu ular body of glass, havinga'hollow evacuated cylindrical wall portion, said wall portion beingformed of an inner and an outer wall having the greatest portion oftheir sides in sub- 'stantially parallel confronting relation toeachother, said hollow walls being partially filled with a mass of aluminiumturnings, and a conductor within said hollow wall in electrical contactwith said mass and extending out of said wall so as to be able to beelectrically connected to a source of current.

26. As an article of manufacture, an electrode' for apparatus forproducing cold electric discharges, comprising a tubular body of glass,having a hollow evacuated cylindrical wall portion, said wall portionbeing formed of an inner and an outer wall having the greatest portionof their sides in substantially parallel confronting relation to eachother, a loose mass of shot partially filling said hollow wall, and aconductor leading from abroad into said hollow wall and beingelectrically connected to said mass of shot.

27. As an article of manufacture, an electrode for apparatus forproducing cold electric discharges, comprising a tubular body of glass,having a hollow evacuated cylindri- .cal wall portion, said wall portionbeing formed of an inner and an outer wall having the greatest portionof their sides in substantially parallel confronting relation to eachother, conducting means within said hollow wall portion in contact withthe greatest part of said inner sides of said inner and outer walls, andmeans for electrically connecting said conducting means to an outerelectric potential.

28. In an apparatus for producing cold electric discharges, a pair ofelectrodes, one of said electrodes comprising a glass tube having ahollow evacuated wall portion, said wall portion being formed of aninner and an outer wall having the greatest portion of their sides insubstantially parallel confronting relation to each other, conductingmeans within said hollowwall portion in contact with the greatest partof the sides of said inner and outer walls, and means for electricallyconnecting said conducting means and the other of said electrodes to asource of electric current.

In testimony whereof I afiix my signature.

J OHANNES KUI-ILEN SCHMIDT.

